The present invention relates to a pneumatic tire and a method of manufacturing the same wherein a puncture sealant is sealed in a space provided along the inside of the tread portion of the tire.
In the laid-open Japanese Patent application JP-A-11-216781, a pneumatic tire is disclosed, wherein, as shown in FIG. 6, a puncture sealant (g) is sealed in a space (j) provided along the inside of the tread portion. The space (j) is formed by interposing an anti-adhesive sheet (c) between an outer rubber (a) and an inner rubber (b). In this tire, depending on the material of the anti-adhesive sheet (c), there is a possibility that the anti-adhesive sheet (c) remaining in the finished tire is torn into shreds through long or heavy use.
On the other hand, it is effectual for sealing puncture holes especially relatively large holes to mix fiber into a sealant.
However, if a sealant including such fiber is used in the above-mentioned tire, there is a possibility that the fiber is caught on the shreds, and as a result, the puncture sealing effect decreases and further the rotational balance of the tire, especially high speed balance deteriorates. Thus, it is difficult to mix fiber into the sealant.
It is therefore, an object of the present invention to provide a pneumatic tire and a method of manufacturing the same, in which such fiber can be mixed into a sealant without the above-mentioned problems, and thus the self-sealing performance is improved.
According to one aspect of the present invention, a pneumatic tire comprises a tread portion provided along the inside thereof with a circumferentially extending bag-like portion, the bag-like portion formed by interposing an anti-adhesive sheet for preventing adjacent materials from bonding each other, the bag-like portion filled with a sealant for self-sealing punctures, the sealant including a substance which dissolves the anti-adhesive sheet, whereby the bag-like portion is filled with the sealant including the anti-adhesive sheet in solution.